转炉熔渣低温气化脱磷行为

周朝刚; 陈庆功; 艾立群; 王书桓; 薛月凯; 陈虎

doi:10.13228/j.boyuan.issn0449-749x.20220268

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钢铁 ›› 2022, Vol. 57 ›› Issue (11) : 64-76. DOI: 10.13228/j.boyuan.issn0449-749x.20220268

炼钢

转炉熔渣低温气化脱磷行为

周朝刚^1,2, 陈庆功^1,2, 艾立群^1,2, 王书桓^1,2, 薛月凯^1,2, 陈虎³

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Dephosphorization behavior by low temperature gasification of converter slag

周朝刚^1,2, 陈庆功^1,2, 艾立群^1,2, 王书桓^1,2, 薛月凯^1,2, 陈虎³

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摘要

在低温下脱磷转炉熔渣中的磷质量分数过高往往是限制转炉渣循环利用的重要因素,因此如何有效降低转炉熔渣中磷质量分数成为众多钢铁企业迫切需要解决的重点问题之一。基于此,从理论分析和工业试验角度,并结合XRD、SEM-EDS和拉曼光谱等试验手段进一步分析研究了理论热力学条件、转炉渣熔点、矿相结构和炉渣结构对低温气化脱磷的影响。通过理论分析表明,较高温度、较低的FeO含量和碱度有利于低温气化脱磷反应。工业试验结果表明,当终点温度为1 350～1 360 ℃、转炉渣FeO质量分数为25%～35%、碱度控制为1.2～2.5时,气化脱磷率可以达到30%以上。当炉渣碱度小于1.25、FeO质量分数小于35%时,适当地提高炉渣碱度和FeO含量能促进炉渣熔点降低,进而有利于低温气化脱磷反应的发生。XRD和SEM-EDS分析结果表明,转炉渣主要由富磷相、基体相和RO相组成,其中Si、P、Ca质量分数高的Ca₂SiO₄-Ca₃(PO₄)₂富磷相的存在不利于低温气化脱磷反应发生,Fe、Mn等金属氧化物质量分数高的RO相和基体相的存在有利于低温气化脱磷。通过转炉渣拉曼光谱分析表明,当转炉渣硅氧四面体结构Qⁿ(n=1,2,3)相对含量较低时,渣中聚合度降低,且Ca₃Si₂O₇相含量较少,炉渣流动性较好,此种渣结构有利于低温气化脱磷。通过本研究可以为钢铁企业实现脱磷转炉渣的二次利用提供借鉴。

Abstract

The high phosphorus content in the dephosphorization converter slag at low temperature limits the recycling of the converter slag. Therefore, how to effectively reduce the phosphorus content in the slag has become one of the key issues that many iron and steel enterprises urgently need to solve. Based on this, the effects of theoretical thermodynamic conditions, melting point of converter slag, mineral phase structure and microstructure of slag on low-temperature gasification dephosphorization were further analyzed and studied from the perspective of theoretical analysis and industrial experiment, combined with XRD, SEM-EDS and Raman spectroscopy. Theoretical analysis shows that higher temperature, lower FeO mass fraction and alkalinity are beneficial to the low temperature gasification dephosphorization reaction; the industrial test results show that the gasification dephosphorization rate can reach over 30% when the terminal temperature, mass percent of FeO and alkalinity of converter slag are controlled in the range of 1 350-1 360 ℃, 25%-35% and 1.2-2.5 respectively. When the basicity and mass percent of FeO of slag are lower than 1.25 and 35% respectively, properly increasing the basicity and mass percent of FeO of slag can promote the melting point of slag to decrease, which is conducive to the occurrence of low-temperature gasification dephosphorization reaction. XRD and SEM-EDS analysis results show that the converter slag is mainly composed of phosphorus-rich phase, matrix phase and RO phase. Among them, the existence of Ca₂SiO₄-Ca₃(PO₄)₂ phosphorus-rich phase with high mass fraction of Si, P and Ca is not conducive to low-temperature gasification dephosphorization, while the existence of RO phase and matrix phase with high mass fraction of metal oxides such as Fe and Mn is conducive to low-temperature gasification dephosphorization. The Raman spectrum analysis of converter slag shows that when the relative content of the silicon-oxygen tetrahedral structure Qⁿ(n=1,2,3) in the converter slag is low, the degree of the polymerization in the slag decreases and the content of the Ca₃Si₂O₇ phase is less, so that the fluidity of converter slag is better. This slag structure is conducive to low temperature gasification dephosphorization. This study can provide reference for iron and steel enterprises to realize the secondary utilization of dephosphorization converter slag.

关键词

转炉熔渣 / 低温 / 气化脱磷 / 热力学条件 / 矿相结构

Key words

converter slag / low temperature / gasification dephosphorization / thermodynamic conditions / mineralstructure

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周朝刚, 陈庆功, 艾立群, 等. 转炉熔渣低温气化脱磷行为[J]. 钢铁, 2022, 57(11): 64-76 https://doi.org/10.13228/j.boyuan.issn0449-749x.20220268

ZHOU Chao-gang, CHEN Qing-gong, AI Li-qun, et al. Dephosphorization behavior by low temperature gasification of converter slag[J]. Iron and Steel, 2022, 57(11): 64-76 https://doi.org/10.13228/j.boyuan.issn0449-749x.20220268

参考文献

[1] 周朝刚, 杨会泽, 艾立群, 等. 转炉含磷钢渣循环利用技术的研究现状及展望[J].钢铁,2021,56(2):22. (ZHOU Chao-gang, YANG Hui-ze, AI Li-qun, et al. Research status and prospect of recycling technology of converter slag containing phosphorus[J]. Iron and Steel, 2021,56(2):22.)
[2] ZHANG X, CHEN J, JIANG J, et al. The potential utilization of slag generated from iron and steelmaking industries: A review[J]. Environ Geochem Health, 2020, 42: 1321.
[3] ZHAO J H, YAN P Y, WANG D. M. Research on mineral characteristics of converter steel slag and its comprehensive utilization of internal and external recycle[J]. Journal of Cleaner Production, 2017, 156(4): 50.
[4] 梁强, 曾加庆, 齐渊洪. 含磷炉渣处理技术的回顾与展望[J]. 钢铁, 2015, 50(1): 69.(LIANG Qiang, ZENG Jia-qin, QI Yuan-hong. Retrospect and prospect of the technology of phosphatic slag treatment[J]. Iron and Steel, 2015, 50(1):69.)
[5] 杜传明, 于耀辉, 袁磊, 等. 钢渣中磷分离及回收的研究现状和发展趋势[J]. 钢铁, 2020, 55(12): 1. (DU Chuan-ming, YU Yao-hui, YUAN Lei, et al. Research status and development trend of phosphorus separation and recovery from steelmaking slag[J]. Iron and Steel, 2020, 55(12): 1.)
[6] GUO J L, BAO Y P, WANG M. Steel slag in China: Treatment, recycling, and management[J]. Waste Management, 2018, 78(4): 318.
[7] Dippenaar R. Industrial uses of slag (the use and re-use of iron and steelmaking slags)[J]. Ironmaking and Steelmaking, 2005, 32(1): 35.
[8] 郝华强,王书桓,张朝发,等. 转炉热态熔渣脱磷及循环利用生产实践[J]. 中国冶金, 2018, 28(6): 56. (HAO Hua-qiang, WANG Shu-huan, ZHANG Chao-fa, et al. Dephosphorization and recycle utilization practice of molten slag in converter[J]. China Metallurgy, 2018, 28(6): 56.)
[9] 韩凯峰, 韩少伟, 朱良, 等. 基于共存理论的转炉脱磷热力学分析[J]. 中国冶金, 2021, 31(10): 17. (HAN Kai-feng, HAN Shao-wei, ZHU Liang, et al. Thermodynamic analysis of dephosphorization in converter based on ion and molecule coexistence theory[J]. China Metallurgy, 2021, 31(10):17.)
[10] Hideki O, Kobata K, Usui T. Carbon reduction rate of phosphorus in oxide melt[J]. Journal of JSEM, 2012, 12(s):209.
[11] Morita K, Guo M, Oka N, et al. Resurrection of the iron and phosphorus resource in steel-making slag[J]. Journal of Material Cycle and Waste Management, 2002, 4(2): 93.
[12] 宫下芳雄, 柳井明, 山田健三, 等. 製鋼溶融スラクの処理方法: 日本, 特开昭51-121030[P]. 1975-04-16.
[13] 郭瑞华, 王书桓, 李晨晓, 等. 焦炭还原脱磷转炉熔渣的气化脱磷试验[J]. 钢铁, 2020, 55(9): 118. (GUO Rui-hua, WANG Shu-huan, LI Chen-xiao, et al. Experimental on coke reduction dephosphorization converter slag gasification dephosphorization[J]. Iron and Steel, 2020, 55(9): 118.)
[14] 王书桓, 吴艳青, 徐志荣, 等. 硅还原转炉熔渣气化脱磷热力学分析[J]. 炼钢, 2008, 24(1): 31.(WANG Shu-huan, WU Yan-qing, XÜ Zhi-rong, et al. Thermodynamic analysis on gasificating dephosphorization of converter slag by silicon reduction[J]. Steelmaking, 2008, 24(1): 31.)
[15] 么洪勇. 转炉溅渣护炉冶炼因素对气化脱磷的影响[J]. 钢铁钒钛, 2017, 38(6): 108. (MO Hong-yong. Effect of slag splashing on gasification dephosphorization in converter[J]. Iron Steel Vanadium Titanium, 2017, 38(6): 108.)
[16] 周朝刚, 艾立群, 王书桓, 等. 气化脱磷机理及对下炉次冶炼过程的影响研究[J]. 钢铁钒钛, 2018, 39(6): 129. (ZHOU Chao-gang, AI Li-qun, WANG Shu-huan, et al. Study on mechanism of gasification dephosphorization and influence of next heat smelting process[J]. Iron Steel Vanadium Titanium, 2018, 39(6): 129.)
[17] 黄希祜. 钢铁冶金原理[M]. 北京:冶金工业出版社, 2002. (HUANG Xi-gu. Principles of Iron and Steel Metallurgy[M]. Beijing: Metallurgical Industry Press, 2002.)
[18] 李晨晓, 赵定国, 薛月凯, 等. 转炉渣微区CaO-SiO₂-FeO氧化物分布特性研究[J]. 硅酸盐通报, 2019, 38(9): 2967. (LI Chen-xiao, ZAHO Ding-guo, XUE Yue-kai, et al. Study on oxides distribution behavior of CaO-SiO₂-FeO converter slag micro-area[J]. Bulletin of the Chinese Ceramic Society, 2019, 38(9): 2967.)
[19] Masanori N, Nobuhiro M, Sun-Joong K, et al. Fundamental experiment to extract phosphorous selectively from steelmaking slag by leaching[J]. ISIJ International, 2014, 54(8):1983.
[20] 杨健. 含铬钢渣制备微晶玻璃及一步热处理研究[D]. 北京:北京科技大学, 2016. (YANG Jian. Glass-ceramics Made from Cr-containing Steel Slag and One-step Heat Treatment Research[D]. Beijing:University of Science and Technology Beijing, 2016.)
[21] SUN G Q, REN K, WANG Y L, et al. Fabrication of highly conducting nickel-coated graphite composite particles with low Ni content for excellent electromagnetic properties[J]. Journal of Alloys and Compounds, 2020, 834: 155142.
[22] 周朝刚, 胡锦榛, 陈虎, 等. 基于高FeO转炉渣的钢液脱磷行为[J]. 钢铁, 2021, 56(7): 63. (ZHOU Chao-gang, HU Jin-zhen, CHEN Hu, et al. Dephosphorization behavior of molten steel based on high FeO converter slag[J]. Iron and Steel, 2021, 56(7): 63.)
[23] 韩啸, 周朝刚, 李晶, 等. 转炉脱磷渣物相结构对脱磷的影响[J]. 钢铁研究学报, 2016, 28(9): 40. (HAN Xiao, ZHOU Chao-gang, LI Jing, et al. Effect of phase structure of converter dephosphorization slag on dephosphorization[J]. Journal of Iron and Steel Research, 2016, 28(9): 40.)
[24] ZHAO J H, YAN P Y, WANG D M. Research on mineral characteristics of converter steel slag and its comprehensive utilization of internal and external recycle[J]. Journal of Cleaner Production, 2017, 156(4): 50.
[25] ZHOU C G, CHEN Q G, JI Y, et al. Effect of converter dust on phosphorus migration behavior in molten iron[J/OL]. ISIJ International, 2022. https://doi.org/10.2355/isijinternational.ISIJINT-2022-249.
[26] Wang Z J, Shu Q F, Sridhar S, et al. Effect of P₂O₅ and Fe_tO on the viscosity and slag structure in steelmaking slags[J]. Metallurgical and Materials Transactions B, 2015, 46(2):758.
[27] 张蕊,贾吉祥,刘承军,等.转炉渣中磷的微观结构行为[J].东北大学学报(自然科学版),2021,42(5):646. (ZHANG Rui, JIA Ji-xiang, LIU Cheng-jun, et al. Microstructure behaviors of phosphorus in converter slag[J]. Journal of Northeastern University(Natural Science), 2021,42(5):646.)
[28] Sajid M, Bai C, Aamir M, et al. Understanding the structure and structural effects on the properties of blast furnace slag (BFS)[J]. ISIJ International, 2019, 59(7):1153.
[29] Tilocca A, Cormack A N. Structural effects of phosphorus inclusion in bioactive silicate glasses[J]. The Journal of Physical Chemistry B, 2007, 111(51): 14256.
[30] ZHOU C, JI Y, CHEN Q, et al. Effect of P₂O₅ addition on enrichment behaviour of phosphorus in CaO-SiO₂-FeO-P₂O₅ slag[J/OL]. Ironmaking and Steelmaking, 2022. https://doi.org/10.1080/03019233.2022.2102337.
[31] Frantz J D, Mysen B O. Raman spectra and structure of BaO-SiO₂, SrO-SiO₂ and CaO-SiO₂ melts to 1 600 ℃[J]. Chemical Geology, 1995, 121(1/2/3/4): 155.
[32] Wang Z, Sun Y, Sridhar S, et al. Effect of Al₂O₃ on the viscosity and structure of CaO-SiO₂-MgO-Al₂O₃-Fe_tO slags[J]. Metallurgical and Materials Transactions B, 2015, 46(2): 537.
[33] PANG Z, LÜ X, YAN Z, et al. Transition of blast furnace slag from silicate based to aluminate based: Electrical conductivity[J]. Metallurgical and Materials Transactions B, 2019, 50(1): 385.
[34] CONG F, GAO L, JUE T, et al. Effects of MgO/Al₂O₃ ratio on viscous behaviors and structures of MgO-Al₂O₃-TiO₂-CaO-SiO₂ slag systems with high TiO₂ content and low CaO/SiO₂ ratio[J]. Transactions of Nonferrous Metals Society of China, 2020, 30(3): 800.
[35] YAN W, ZHANG G, LI J. Viscosity and structure evolution of CaO-SiO₂-based mold fluxes with involvement of CaO-Al₂O₃-based tundish fluxes[J]. Ceramics International, 2020, 46(9): 14078.
[36] Lin C C, Chen S F, Leung K S, et al. Effects of CaO/P₂O₅ ratio on the structure and elastic properties of SiO₂-CaO-Na₂O-P₂O₅ bioglasses[J]. Journal of Materials Science: Materials in Medicine, 2012, 23(2): 245.
[37] ZHANG R, MIN Y, WANG Y, et al. Structural evolution of molten slag during the early stage of basic oxygen steelmaking[J]. ISIJ International, 2020, 60(2): 212.
[38] Saitoh A, Brow R K, Hoppe U, et al. The structure and properties of xZnO-(67-x) SnO-P₂O₅ glasses:(I) Optical and thermal properties, Raman and infrared spectroscopies[J]. Journal of Non-Crystalline Solids, 2018, 484(1): 132.
[39] 马进进, 尤静林, 王建, 等. CaO-SiO₂ 二元系晶体和玻璃的拉曼光谱研究[J].光谱学与光谱分析,2018,38(增刊1):245. (MA Jin-jin, YOU Jin-lin, WANG Jian, et al. Study on the crystals and glasses of binary CaO-SiO₂ system by raman spectroscopy[J]. Spectroscopy and Spectral Analysis, 2018, 38(s1):245.)